1
*RoHS Directive 2002/95/EC Jan 27 2003 including Annex.
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
MX5A-12SA SMT Non-Isolated Power Module
Features
■Industry standard surface mount device
■RoHS compliant*
■Output voltage programmable from
0.75 Vdc to 5.0 Vdc via external resistor
■Up to 5 A output current
■Up to 92 % efficiency
■Small size, low profile
■Cost-efficient open frame design
■Low output ripple and noise
■High reliability
■Remote on/off
■Output overcurrent protection
(non-latching)
■Constant switching frequency (300 kHz)
■Wide operating temperature range
Description
Bourns®MX5A-12SA is a non-isolated DC-DC converter
offering designers a cost and space-efficient solution with
standard features such as remote on/off, precisely regulated
programmable output voltage and overcurrent and over-
temperature protection. These modules deliver up to 5 A of
output current with load efficiency of 92 % at 5 V output.
Stress in excess of absolute maximum ratings may cause permanent damage to the device. Device reliability may be affected if
exposed to absolute maximum ratings for extended time periods.
Characteristic Min. Max. Units Notes & Conditions
Continuous Input Voltage -0.3 15.0 Vdc
Operating Temperature Range -40 +85 °C See Thermal Considerations section
Storage Temperature -55 +125 °C
Absolute Maximum Ratings
Unless otherwise specified, specifications apply over all input voltage, resistive load and temperature conditions.
Caution: The power modules are not internally fused. An external input line fast-blow fuse with a maximum rating of 6 A is required.
See the Safety Considerations section of this data sheet.
Electrical Specifications
■Intermediate Bus architecture
■Distributed power applications
■Workstations and servers
■Telecom equipment
■Enterprise networks including LANs/WANs
■Latest generation ICs (DSP, FPGA, ASIC) and microprocessor powered applications
Applications
*RoHS COMPLIANT
Characteristic Min. Nom. Max. Units Notes & Conditions
Operating Input Voltage 10.0 14.0 Vdc
Maximum Input Current - 3.5 Adc Over Vin range, Iomax, Vout = 5 Vdc
Input No Load Current Vin = 12 Vdc, Io= 0 A, mod. enabled,
26 mA -Vout = 0.75 Vdc
70 mA -Vout = 5.0 Vdc
Input Stand-by Current 1.6 mA Vin = 5.0 Vdc, module disabled
Inrush Transient 0.4 A2s
Input Reflected Ripple Current 40 mAp-p
Input Ripple Rejection 30 dB 120 Hz
How to Order
M X 5A - 12 S A
Configuration
• M = Surface Mount Device
Internal Identifier
Output Current (Amps)
Input Voltage (V)
Outputs
• S = Single
Output Voltage (V)
• A = Adjustable
Fixed output voltage parts and optional features available; contact factory.
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
2
MX5A-12SA SMT Non-Isolated Power Module
Electrical Specifications (Continued)
Characteristic Min. Nom. Max. Units Notes & Conditions
Output Voltage Setpoint Accuracy -2.0 2.0 % Vo,set Vin min, Iomax, TA= 25 °C
Output Voltage Tolerance -3.0 3.0 % Vo,set Over all rated in out voltage, load and
temperature conditions
Voltage Adjustment Range 0.7525 5.5 Vdc
Line Regulation 0.3 % Vo,set
Load Regulation 0.3 % Vo,set
Temperature Regulation 0.4 % Vo,set
Output Current 0.0 5.0 Adc
Output Current Limit Inception (Hiccup Mode) 200 % Iomax
Output Short Circuit Current 2 Adc Vo≤250 mV – Hiccup Mode
Output Ripple and Noise Voltage 1 µF ceramic/10 µF tantalum capacitors
RMS 15 30 mVrms 5 Hz to 20 MHz bandwidth
Peak-to-Peak 30 75 mVpk-pk
External Capacitance
- ESR ≥1 mΩ1000 µF
- ESR ≥10 mΩ3000 µF
Efficiency 81.5 % Vo,set = 1.2 Vdc
(Vin = 5 Vdc, TA= 25 °C, Full Load) 84.0 % Vo,set = 1.5 Vdc
85.0 % Vo,set = 1.8 Vdc
87.0 % Vo,set = 2.5 Vdc
89.0 % Vo,set = 3.3 Vdc
92.0 % Vo,set = 5.0 Vdc
Switching Frequency 300 kHz
Dynamic Load Response 1 µF ceramic/10 µF tantalum capacitor
2.5 A to 5 A; 5 A to 2.5 A; 200 mV Peak Deviation
(∆i/∆t = 2.5 A/µs; 25 °C) 25 µs Settling Time (Vo<10 % peak deviation)
2 x 150 µF polymer capacitors
2.5 A to 5 A; 5 A to 2.5 A; 75 mV Peak Deviation
(∆i/∆t = 2.5 A/µs; 25 °C) 50 µs Settling Time (Vo<10 % peak deviation)
General Specifications
Characteristic Nom. Units Notes & Conditions
Calculated MTBF 10,000,000 hours
Weight 2.2 g
(0.08) (oz.)
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications. 3
MX5A-12SA SMT Non-Isolated Power Module
Feature Specifications
Characteristic Min. Nom. Max. Units Notes & Conditions
Remote Enable
Open = On (Logic Low) 0.4 Vdc 10 µA max.
Low = Off (Logic High) >2.5 14 Vdc 1 mA max.
Turn-On Delay and Rise Times
Case 1: On/Off Low – Vin Applied 2.5 msec
Case 2: Vin Applied, then On/Off Set Low 2.5 msec
Case 3: Output Voltage Rise 3.0 msec (10 %-90 % of Vosetting)
Output Voltage Overshoot 1 % Vo, set Iomax, Vin=5.5, TA=25 °C
Overtemperature Protection 135 °C See Thermal Consideration section
Input Undervoltage Lockout
-Turn-on Threshold 8.2 V
-Turn-off Threshold 8.0 V
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
4
MX5A-12SA SMT Non-Isolated Power Module
Characteristic Curves
The curves provided below are typical characteristics for the MX5A-12SA modules at 25 °C. For any specific test configurations or any
specific test requests, please contact Bourns.
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 1 Efficiency vs. Output Current (V = 1.2 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 4 Efficiency vs. Output Current (V = 2.5 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 2 Efficiency vs. Output Current (V = 1.5 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 5 Efficiency vs. Output Current (V = 3.3 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 3 Efficiency vs. Output Current (V = 1.8 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
100.0
90.0
95.0
85.0
80.0
75.0
70.0
1.0 2.0 3.0 4.0
Output Current (A )
Fig. 6 Efficiency vs. Output Current (V = 5.0 V )
dc
out dc
Efficiency (%)
5.0
Vin=14 V
Vin=12 V
Vin=10 V
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
MX5A-12SA SMT Non-Isolated Power Module
Characteristic Curves (Continued)
Fig. 10 Transient Response - 2.5 A - 5 A Step
(V = 3.3 V )
odc
Output Voltage
V (100 mV/div)
o
Output Current
I (1.3 A/div)
o
Output Voltage: 100 mVolt 5 µs
Output Current (1.3 A/Div): 2 Volt 5 µs
Time (5 µs/div)
oo
Fig. 11 Transient Response - 5 A - 2.5 A Step
(V = 3.3 V )
odc
Output Voltage
V (100 mV/div)
o
Output Current
I (1.3 A/div)
o
Output Voltage: 100 mVolt 5 µs
Output Current (1.3 A/Div): 2 Volt 5 µs
Time (5 µs/div)
Fig. 12 Transient Response - 2.5 A - 5 A Step
(V = 12.0 V, V = 12 V , C = 2x100 µF Polymer Capacitors)
o dc ext
Output Voltage
V (100 mV/div)
o
Output Current
I (0.9 A/div)
o
Output Voltage: 100 mVolt 10 µs
Output Current (0.9 A/Div): 2 Volt 10 µs
Time (10 µs/div)
Fig. 8 Typical Output Ripple and Noise
(V = 12.0 V, V = 0.75 V, I = 5.0 A)
in o o
Output Voltage
V (10 mV/div)
Full Load: 50 mVolt 2.5 µs
No Load: 50 mVolt 2.5 µs
Half Load: 50 mVolt 2.5 µs
Full Load: 10 mVolt 2.5 µs
No Load: 10 mVolt 2.5 µs
Half Load: 10 mVolt 2.5 µs
Time (2.5 µs/div)
Fig. 9 Typical Output Ripple and Noise
(V = 12.0 V, V = 3.3 V, I = 5.0 A) in
in oo
Output Voltage
V (50 mV/div)
Time (2.5 µs/div)
0.00
2.00
4.00
6.00
8.006.00 10.00
Input Voltage (V )
Fig. 7 Input Voltage vs. I and V
dc
oo
(V = 2.5 V , I = 6.0 A)
oodc
Input Current (A)/
Output Voltage (Vdc)
12.00
Iin, Adc
Vo, Vdc
5
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
6
MX5A-12SA SMT Non-Isolated Power Module
Characteristic Curves (Continued)
?
?
??
Fig. 14 Typical Start-up using Positive Remote On/Off
(V = 12 V , V = 3.3 V , I = 5 A)
in dc dcoo
Output Voltage: 1 Volt 1 ms
On/Off Voltage: 5 Volt 1 ms
Output Voltage:
1 Volt 1 ms
On/Off Voltage:
5 Volts 1 ms
Time (1 ms/div)
Output Voltage
V (100 mV/div)
o
Output Current
I (0.9 A/div)
o
??
On/Off Voltage
V (5 V/div)
on/off
Output Voltage
V (1 V/div)
o
??
On/Off Voltage
V (5 V/div)
on/off
Output Voltage
V (1 V/div)
o
Fig. 13 Transient Response - 5 A - 2.5 A Step
(V = 12 V ,V = 3.3 V , C = 2x100 µF Polymer Caps)
in o dcdc ext
Output Voltage: 100 mVolt 10 µs
Output Current (0.9 A/Div): 2 Volt 10 µs
Time (5 µs/div)
Fig. 15 Typical Start-up using Negative Remote On/Off
with Low-ESR External Capacitors (10x100 µF Polymer)
(V = 12 V , V = 3.3 V , I = 5.0 A, C = 1000 µF)
in dc dcooo
Time (1 ms/div)
Output Voltage:
1 Volt 1 ms
Input Voltage:
5 Volt 1 ms
???
Input Voltage
V (5 V/div)
in
Output Voltage
V (1 V/div)
o
Fig. 16 Typical Start-up with Application of V
(V = 12 V , V = 3.3 V , I = 5 A)
in
in
dc dcoo
Time (1 ms/div)
Output Voltage:
500 mVolt 1 ms
On/Off Voltage:
5 Volt 1 ms
??
On/Off Voltage
V (5 V/div)
on/off
Output Voltage
V (0.5 V/div)
o
Fig. 17 Typical Start-up using Remote On/Off with Prebias
(V = 12 V , V = 1.8 V , I = 1 A, V = 1 V )
in dc dc dcbiasoo
Time (1 ms/div)
Output Current (4 A/div): 20 mVolt 25 ms
??
Output Current
I (4 A/div)
o
Fig. 18 Output Short Circuit Current
(V = 12.0 V , V = 0.75 V )
in dc dco
Time (5 ms/div)
???
??
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications. 7
MX5A-12SA SMT Non-Isolated Power Module
Characteristic Curves (Continued)
6
5
4
3
2
1
02515 4535 6555 75
Ambient Temperature (°C)
Output Current (A)
85
200 LFM
0 LFM
100 LFM
Fig. 19 Derating Output Current vs.
Local Ambient Temp. and Airflow
(V = 12.0 V , V = 0.75 V )
in dc dco
Ambient Temperature (°C)
Fig. 22 Derating Output Current vs.
Local Ambient Temp. and Airflow
(V = 12.0 V , V = 5.0 V )
in dc dco
Ambient Temperature (°C)
Fig. 20 Derating Output Current vs.
Local Ambient Temp. and Airflow
(V = 12.0 V , V = 1.8 V )
in dc dco
Ambient Temperature (°C)
Fig. 21 Derating Output Current vs.
Local Ambient Temp. and Airflow
(V = 12.0 V , V = 3.3 V )
in dc dco
7
5
4
6
3
2
1
02515 4535 6555 75
Output Current (A)
85
200 LFM
0 LFM
100 LFM
7
5
4
6
3
2
1
02515 4535 6555 75
Output Current (A)
85
200 LFM
0 LFM
100 LFM
7
5
4
6
3
2
1
02515 4535 6555 75
Output Current (A)
85
200 LFM
0 LFM
100 LFM
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
8
MX5A-12SA SMT Non-Isolated Power Module
Operating Information
Remote On/Off
The MX5A-12SA comes standard with Active LOW with Negative On/Off logic, i.e., OPEN or LOW (< 0.4 V) will turn ON the device. To
turn the device OFF, increase the voltage level above 2.4 V, placing the part into low dissipation sleep mode. The signal level of the
On/Off pin input is defined with respect to ground.
MX5A-12SA
Fig. 23 Circuit Configuration for using Negative Logic On/Off
Input Considerations
The input must have a stable low impedance AC source for optimum performance. This can be accomplished with external ceramic
capacitors, tantalum capacitors and/or polymer capacitors. Using low impedance tantalum capacitors requires about 20 µF per Amp
and an ESR of 250 mΩper Amp of output current. For a 5 A converter, tantalum capacitors with a combined value of 100 µF and
50 mΩwould be adequate. This can be implemented with (2) 47 µF tantalum capacitors with an ESR of 100 mΩ. Ceramic capacitors
are also recommended to reduce high frequency ripple on the input.
Output Considerations
To maintain the specified output ripple and transient response, external capacitors must be used. An external 1 µF ceramic capacitor in
parallel with a 10 µF low ESR tantalum capacitor will usually meet the specified performance. Improved performance can be achieved
by using more capacitance. Low ESR polymer capacitors may also be used. Two 100 µF, 9 mΩor lower ESR capacitors are
recommended.
Safety Information
In order to comply with safety requirements the user must provide a fuse in the unearthed input line. This is to prevent earth being
disconnected in the event of a failure.
The converter must be installed as per guidelines outlined by the various safety approvals if safety agency approval is required for the
overall system.
Overtemperature Protection
The device will shut down if it becomes too hot (typically 135 °C – at controller IC). Once the converter cools, it automatically restarts.
This feature does not guarantee the converter won’t be damaged by temperatures above its rating.
Overcurrent Protection
The device has an internally set output current limit to protect it from overloads, placing the unit in hiccup mode. Once the overload is
removed the converter automatically resumes normal operation. No user adjustments are available. An external fuse in series with the
input voltage is also required for complete overload protection.
Input Undervoltage Lockout
The device operation is disabled if the input voltage drops below the specified input range. Once the input returns to the specified
range operation automatically resumes. No user adjustments are available.
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications. 9
Output Voltage Setting
The output voltage can be programmed to any voltage between 0.75 Vdc and 5.5 Vdc by connecting a single resistor between the trim
pin and the GND pin of the module, as shown in Fig. 24 below.
If left open circuit the output voltage will default to 0.75 Vdc. The correct Rtrim value for a specific voltage can be calculated using the
following equation:
Rtrim = [10.5/(Vo-0.7525)-1] KΩ
For example, to set the MX5A-12SA to 3.3 V the following
Rtrim resistor must be used:
Rtrim = [10.5/(3.3-0.7525)-1] KΩ
Rtrim = 3.122 kΩ,
The closest standard 1 % E96 value is 3.09 kΩ.
Table 1 provides the Rtrim values required for some common output
voltage set points.
MX5A-12SA SMT Non-Isolated Power Module
Operating Information (Continued)
ON/OFF
VIN (+) VO (+)
TRIM
GND
LOAD
Rtrim
Fig. 24 Circuit Configuration to Program Output
Voltage using an External Resistor
MX5A-12SA Rtrim Values
Vo (V) Rtrim (kΩ) 1 % Value
0.75 Open Open
1.2 22.46 22.6
1.5 13.05 13.0
1.8 9.024 9.09
2.0 11.78 11.8
2.5 5.009 4.99
3.3 3.122 3.09
5.0 1.472 1.47
Table 1
MX5A-12SA Vtrim Values
Vo (V) Vtrim (V)
0.75 Open
1.2 0.670
1.5 0.650
1.8 0.630
2.5 0.583
3.3 0.530
5.0 0.4166
Table 2
The output voltage of the device can also be set by applying a voltage between the TRIM and GND pins. The Vtrim equation can be
written as follows:
Vtrim = (0.7 – 0.0667 x{Vo – 0.7225))
To set Vo = 3.3 V, the Vtrim required would therefore be 0.530 V.
Table 2 below provides the Vtrim values required for some common output voltage set points.
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
10
MX5A-12SA SMT Non-Isolated Power Module
Operating Information (Continued)
Voltage Margining
Output voltage margining can be implemented as follows:
1) Trim-up: Connect a resistor, Rm-up, from the Trim pin to the ground pin for adjusting the voltage upwards, and
2) Trim-down: Connect a resistor, Rm-down, from the Trim pin to the output pin for adjusting the voltage downwards.
Please consult your local Bourns Field Applications Engineer for more details and the calculation of the required resistor values.
Vin
On/Off
Vo
Vo
Q2
Q1
Rmargin-up
Rmargin-down
Rtrim
Trim
COM
Fig. 25 Circuit Configuration for Margining Output Voltage
Sufficient cooling must always be considered to ensure reliable operation, as these devices operate in a variety of thermal environments.
Factors such as ambient temperature, airflow, power dissipation and reliability must be taken into consideration.
The data presented in Figures 19 to 22 is based on physical test results taken in a wind tunnel test. The test set-up is shown in
Figure 27.
The thermal reference points are (1) Tref1 = temp at dual Mosfet, as shown in Figure 26, and (2) Tref2 = temp at controller IC. For reliable
operation, neither Tref1 or Tref2 should exceed 115 °C.
Thermal Considerations
Tref1
Air Flow
C2 C3 Q1
C1
L1
Fig. 26 Tref1 Temperature Measurement Location
WIND TUNNEL
Airflow and ambient
temp sensor probes
location
8.1 (0.32)
Air
Flow
25.4 (1.0)
76.2 (3.0)
PCB
UNIT UNDER TEST
n
Fig. 27
Thermal Test Set-up
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications. 11
The MX5A-12SA device has a maximum coplanarity of 100 µm (approx. 0.004 ”), as defined by JESD22-B108.
MX5A-12SA SMT Non-Isolated Power Module
Product Dimensions
Coplanarity
Tin (Sn) plating over nickel (Ni).
Pin Plating Composition
Recommended Pad Layout
VIN ON/OFF
VOUTTRIMGND
20.3
(0.80)
4.83
(0.190)
2.29
(0.090) 1.3
(0.05)
1.5
(0.06)
1.47
(0.058)
8.64
(0.340)
11.43
(0.450)
8.89
(0.350)
4.06
(0.160)
4.57
(0.180)
4.06
(0.160)
DIMENSIONS:
MM
(INCHES)
5.84
(0.230)
MAX.
5.56
(0.219)
REF.
1.57
(0.062)
L1 INDUCTOR
BOTTOM VIEW SIDE VIEW
TOLERANCES:
DECIMAL .X ± 0.5
(0.02)
DECIMAL .XX ± 0.25
(0.010)
VIN
VOUT GNDTRIM
ON/OFF
0.25
(0.010)
17.53
(0.690)
4.57
(0.180)
1.3
(0.05)
RECOMMENDED PAD SIZE: MIN.X
3.05
(0.120)
2.41
(0.095)
MAX.X
3.43
(0.135)
2.79
(0.110)
1.5
(0.06)
8.89
(0.350)
8.64
(0.340)
4.06
(0.160) 4.83
(0.190)
4.06
(0.160)
DIMENSIONS:
MM
(INCHES)
Fig. 28 Product Dimensions
Fig. 29 Recommended Pad Layout
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications.
12
MX5A-12SA SMT Non-Isolated Power Module
Use in Manufacturing Environment
Pick and Place Information
Bourns SMT devices, packaged on tape and reel, are designed (low mass) for automated assembly using standard SMT pick and
place equipment. The centrally located inductor provides the flat surface area to be used for component pick up. Variables such as
nozzle style, nozzle size, handling speed, and placement pressure need to be optimized for best results.
DIMENSIONS:
MM
(INCHES)
9.65
(0.380)
20.3
(0.80)
6.22
(0.245)
11.43
(0.450)
Fig. 30 Pick and Place Location
Packaging Information
Devices come in 44 mm tape and reel, as per EIA-481-2.
PCB Layout for SMT Devices
• Use a solder mask defined pad design.
• See specific datasheet for recommended minimum and maximum pad size.
• Interconnection to internal power planes is typically required.
• “Via-in-pad” design should be avoided in the SMT pads.
• Solder mask should be used to eliminate solder wicking into the vias.
• Low resistance and low inductance PCB layout traces should be used where possible, particularly on the output side.
• A low impedance track between the input ground and output ground is very important to achieve high efficiencies.
Reel Dimensions:
Outside Diameter:
Inside Diameter:
Width:
A
A
SECTION A-A
SECTION B-B
BB
1.50 +0.10/-0.00
(.049 +.004/-0.00)
5.90
(.232)
0.4 ±0.10
(.016 ± .004) 2.00 ± 0.10
(.079 ± .004)
4.00 ± 0.10
(.157 ± .004)
1.75 ± 0.10
(.069 ± .004)
DIA.
2.00 +0.10/-0.00
(.079 +.004/-0.00)
DIA.
20.60
(.811)
20.20 ± 0.10
(.795 ± .004)
40.40 ± 0.10
(1.591 ± .004)
44.00 ± 0.10
1.732 ± .004)
11.70
(.461)
16.00 ± 0.10
(.630 ± .004)
DIMENSIONS:
MM
(INCHES)
330.2
(13.00)
177.8
(7.00)
44.0
(1.73)
Fig. 31 Packaging Tape Detail
Specifications are subject to change without notice.
Customers should verify device performance in their specific applications. 13
MX5A-12SA SMT Non-Isolated Power Module
Use in Manufacturing Environment (Continued)
LONGFORM REV. B 08/06
Asia-Pacific: Tel: +886-2 2562-4117 • Fax: +886-2 2562-4116
Europe: Tel: +41-41 768 5555 • Fax: +41-41 768 5510
The Americas: Tel: +1-951 781-5500 • Fax: +1-951 781-5700
www.bourns.com
Soldering Requirements
Bourns recommends the following temperature profile for use on tin lead solder (Sn-Pb Eutectic) and lead free solder. For lead free
solder, the maximum temperature during the mounting process should not exceed 245 °C. Sufficient time must be allowed to fuse the
plating on the connection to ensure a reliable solder joint. However, the time above 230 °C should not exceed 60 seconds.
Water Washing
A non-clean solder paste system should be used for solder attach onto application boards. The parts are suitable for water washing
applications. However, the user must ensure that the drying process is sufficient to remove all water from the module after washing
and that the module is never powered up prior to the module being fully dried.
Inspection/Rework
Conventional techniques may be employed when replacing a unit in the application. Using a precision dispenser or a suitable mini-
stencil, a suitable volume of solder paste should be applied to the cleaned pads. Reflow can be achieved by standard SMT rework
techniques such as IR or techniques developed for BGA components.
ESD Requirements
Bourns manufactures all models in an ESD controlled environment and all product is supplied in conductive packaging to prevent
ESD damage from occurring before or during shipping. All products must be unpacked and handled using approved ESD control
procedures. Failure to do so may affect the lifetime of the converter.
Storage
The X & XT Series have an MSL rating of 1 per IPC/JEDEC J-STD-033A.
Solder Reflow Profile
0
50
100
150
200
250
300
0 15 30 45 60 75 90 105 120 135 150 165 180 195 210 225 240 255 270 285 300
Time (Seconds)
Temperature (°C)
Preheating Zone
(2 - 4 min. max.)
Soaking Zone
(2 min. max.)
60-90 sec typical
0.5 - 0.6 °C/sec.
Reflow Zone
(90 sec. max.)
30-60 sec. typ.
1.3 - 1.6 °C/sec.
Peak Temp. (Pb Solder)
210-225 °C
Preheat Zone
<2.5 °C/sec.
Peak Temp. (Pb-Free Solder)
245 °C
Cool Down Zone
Fig. 32 Suggested Reflow Profile
